에거박사 교수

Live migration of virtual machines (VM) across distinct physical hosts is an important feature of virtualization technology for maintenance, load-balancing and energy reduction, especially so for data centers operators and cluster service providers. Several techniques have been proposed to reduce the downtime of the VM being transferred, often at the expense of the total migration time. In this work, we present a technique to reduce the total time required to migrate a running VM from one host t

Live migration is one of the key technologies to improve data center utilization, power efficiency, and maintenance. Various live migration algorithms have been proposed; each exhibiting distinct characteristics in terms of completion time, amount of data transferred, virtual machine (VM) downtime, and VM performance degradation. To make matters worse, not only the migration algorithm but also the applications running inside the migrated VM affect the different performance metrics. With service-

In this paper, we propose a fully automatic dynamic scratch-pad memory (SPM) management technique for instructions. Our technique loads required code segments into the SPM on demand at runtime. Our approach is based on postpass analysis and optimization techniques, and it handles the whole program, including libraries. The code mapping is de-termined by solving mixed integer linear programming for-mulation that approximates our demand paging technique. We increase the effectiveness of demand pag

In this paper,we present a dynamic scratchpad memory allocation strategy targeting a horizontally partitioned memory subsystem for contemporary embedded processors. The memory subsystem is equipped with a memory management unit (MMU), and physically addressed scratchpad memory (SPM)is mapped into the virtual address space. A small minicache is added to further reduce energy consumption and improve performance.Using the MMU's page fault exception mechanism, we track page accesses and copy frequen

Checkpointing, i.e., recording the volatile state of a virtual machine (VM) running as a guest in a virtual machine monitor (VMM) for later restoration, includes storing the memory available to the VM. Typically, a full image of the VM's memory along with processor and device states are recorded. With guest memory sizes of up to several gigabytes, the size of the checkpoint images becomes more and more of a concern.

In this work, we present a dynamic memory allocation technique for a novel, horizontally partitioned memory subsystem targeting contemporary embedded processors with a memory management unit (MMU). We propose to replace the on-chip instruction cache with a scratchpad memory (SPM) and a small minicache. Serializing the address translation with the actual memory access enables the memory system to access either only the SPM or the minicache. Independent of the SPM size and based solely on profilin

We propose a code scratchpad memory (SPM) management technique with demand paging for embedded systems that have no memory management unit. Based on profiling information, a postpass optimizer analyzes and optimizes application binaries in a fully automated process. It classifies the code of the application including libraries into three classes based on a mixed integer linear programming formulation: External code is executed directly from the external memory. Pinned code is loaded into the SPM

This paper presents a dynamic scratchpad memory (SPM) code allocation technique for embedded systems running an operating system with preemptive multitasking. Existing SPM allocation schemes do not support multiple tasks or only a fixed number of processes that are known at compile time. These schemes rely on algorithms that select code depending on the size of the SPM. In contemporary portable devices, however, processes are created and terminated on demand and the SPM is shared among them.We i

We present an effective code compression technique to reduce the area and energy overhead of the configuration memory for coarse-grained reconfigurable architectures (CGRA). Based on a statistical analysis of existing code, the proposed method reorders the storage locations of the reconfigurable entities and splits the wide configuration memory into a number of partitions. Code compression is achieved by removing consecutive duplicated lines in each partition. Compressibility is increased by an

The ability to save the state of a running virtual machine (VM) for later restoration is an important tool for home, server, and virtual desktop cloud (VDC) environments in order to achieve optimal and balanced hardware utilization. With guest memory sizes of four to eight gigabytes being the norm the time- and space-overhead of storing VM checkpoints still prevents an effective use of the technique. This work presents a method for fast and space-efficient checkpointing of VMs. Based on the obse

We present an effective code compression technique to reduce the area and energy overhead of the configuration memory for coarse-grained reconfigurable architectures (CGRA). Based on a statistical analysis of existing code, the proposed method reorders the storage locations of the reconfigurable entities and splits the wide configuration memory into a number of partitions. Code compression is achieved by removing consecutive duplicated lines in each partition. Compressibility is increased by an